Infants 30 Child development 18 Infant psychology 15 Infant 12 Psychology 10 Child 9 Child psychology 8 Child Development 6 Child care 6 Children 6 Cognition 5 Developmental psychology 5 Cognition in children 4 Development 4 Diseases 4 Dissertations, Academic (Ph.D) 4 Early childhood education 4 Mortality 4 Myocardial infarction 4 Nutrition 4 Philosophy 4 Pregnancy 4 Research 4 methods 4 Adolescence 3 Birth control 3 Child Psychology 3 Cognition in infants 3 Demography 3 Education 3